Wearable cardiac defibrillation system with flexible electrodes

ABSTRACT

In embodiments, a wearable cardiac defibrillation (WCD) system includes one or more flexible ECG electrodes. The WCD system may have a support structure that is dimensioned to be worn so as to press the electrodes towards the body of the patient. The electrodes may be made from appropriate material so as to flex in order to match a contour of the body of the patient. An advantage over the prior art is that the flexible electrode may make better electrical contact with the patient&#39;s skin, and therefore provide a better ECG signal for the WCD system to perform its diagnosis.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 14/710,799 filed on May 13, 2015, which in turn claims priorityfrom U.S. Provisional Patent Application Ser. No. 62/072,818, filed onOct. 30, 2014, the disclosure of which is hereby incorporated byreference.

BACKGROUND

When people suffer from some types of heart arrhythmias, the result maybe that blood flow to various parts of the body is reduced. Somearrhythmias may even result in a Sudden Cardiac Arrest (SCA). SCA canlead to death very quickly, e.g. within 10 minutes, unless treated inthe interim.

Some people have an increased risk of SCA. People at a higher riskinclude individuals who have had a heart attack, or a prior SCA episode.A frequent recommendation is for these people to receive an ImplantableCardioverter Defibrillator (“ICD”). The ICD is surgically implanted inthe chest, and continuously monitors the person's electrocardiogram(“ECG”). If certain types of heart arrhythmias are detected, then theICD delivers an electric shock through the heart.

After being identified as having an increased risk of an SCA, and beforereceiving an ICD, these people are sometimes given a Wearable CardiacDefibrillator (“WCD”) system. A WCD system typically includes a harness,vest, or other garment that is configured to be worn by the patient. TheWCD system includes a defibrillator and external electrodes, which areattached to the inside of the harness, vest, or other garment. When thepatient wears the WCD system, the external electrodes can help monitorthe patient's ECG. If a shockable heart arrhythmia is detected, then thedefibrillator of the WCD system delivers the appropriate electric shockthrough the patient's body, and thus through the heart.

A challenge in the prior art remains with the monitoring electrodes.Electrodes may need to make good electrical contact with the patient'sskin, without being intrusive or irritating the skin.

BRIEF SUMMARY

The present description gives instances of Wearable CardiacDefibrillator (WCD) systems and electrode components for such systems,the use of which may help overcome problems and limitations of the priorart.

In embodiments, a wearable cardiac defibrillation (WCD) system includesone or more flexible ECG electrodes. The WCD system may have a supportstructure that is dimensioned to be worn so as to press the electrodestowards the body of the patient. The electrodes may be made fromappropriate material so as to flex in order to match a contour of thebody of the patient. An advantage over the prior art is that theflexible electrode may make better electrical contact with the patient'sskin, and therefore provide a better ECG signal for the WCD system toperform its diagnosis.

In embodiments, a wearable cardiac defibrillation (WCD) system includesone or more electrode assemblies. The WCD system may have a supportstructure that is dimensioned to be worn so as to press the electrodeassembly towards the body of the patient. The electrode assembly mayhave an electrode, and a signal terminal electrically coupled to theelectrode. The electrode assembly may have a compressible pillowstructure. The electrode assembly may have a moisture barrier so as totrap moisture from the patient's skin, for better conduction and lateralshifting of the electrode along the patient's skin. The electrodeassembly may have an electrostatic shield between the electrode and thesignal terminal so as to shield the electrode from electrical noise.

Embodiments may result in garments that integrate the disclosedelectrode, and which can be washed with normal household methods. Thisallows for simple cleaning of lotions or patient's sweat from theelectrodes, which may improve patient hygiene and reduce the chance ofskin infections. All of this will add to the patient's overall comfortwith the garment, and thus enhance their compliance with wearing thegarment.

These and other features and advantages of this description will becomemore readily apparent from the Detailed Description, which proceeds withreference to the associated drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of sample components of a Wearable CardiacDefibrillator (WCD) system according to embodiments.

FIG. 2A is a diagram of a detail of a flexible electrode of FIG. 1 thatis made according to embodiments, and is applied to a patient's bodyunder pressure.

FIG. 2B is a diagram of a detail of the electrode of FIG. 2A, as it isdeposited on a flat level surface.

FIG. 3 is a diagram of sample components of a WCD system according toembodiments.

FIG. 4A is a diagram of some components of an electrode assembly of FIG.1 that includes a pillow structure made according to embodiments and isapplied to a patient's body under pressure.

FIG. 4B is a diagram of a detail of the pillow structure of theelectrode assembly of FIG. 4A, as it is deposited on a flat surface.

FIG. 5 is a diagram of sample components of an electrode assembly, whichis made according to embodiments that include a flexible innerconductor.

FIG. 6A is a diagram of sample components of an electrode assembly,which is made according to embodiments that include a flexible innerconductor which has a fabric that is coated with a metal.

FIG. 6B is a top view of a flexible inner conductor of FIG. 6A accordingto an embodiment.

FIG. 7 is a diagram of sample components of an electrode assembly, whichis made according to embodiments that include a moisture barrier.

FIG. 8 is a diagram of sample components of an electrode assembly, whichis made according to embodiments that include an electrostatic shield.

FIG. 9 is a diagram of sample components of an electrode assembly, whichis made according to embodiments that include a cover.

FIG. 10 is a diagram of a sample electrode assembly according to anembodiment.

FIG. 11A is a diagram of sample components of an electrode assembly,which is made according to embodiments that include a moisture barrier.

FIG. 11B is a top view of a main surface of an electrode that may beused in the assembly of FIG. 11A according to an embodiment.

FIG. 12 is a diagram of sample components of an electrode assembly,which is made according to embodiments that include an electrostaticshield.

FIG. 13 is a diagram of sample components of an electrode assembly,which is made according to embodiments that include a cover.

FIG. 14 is a diagram of sample components of an electrode assembly, madeaccording to embodiments that include an electrostatic shield.

FIG. 15 is a diagram of sample components of an electrode assembly, madeaccording to embodiments that include an electrostatic shield and acorresponding reference terminal.

DETAILED DESCRIPTION

As has been mentioned, the present description is about Wearable CardiacDefibrillator (WCD) systems and electrode components for such systems.Embodiments are now described in more detail.

FIG. 1 is a diagram of sample components 100 of a WCD system accordingto embodiments. Components 100 are intended to be worn by a patient 182,typically according to specific instructions. Only a section of the bodyof patient 182 is shown, which can be the torso, or other bodily part.

Components 100 of a WCD system are now described in more detail.Components 100 include a support structure 110, which is shown partlyabstractly in FIG. 1. Support structure 110 can be configured to be wornby patient 182, typically according to a design. Support structure 110can thus be part of a belt, a harness, a garment, a holster, and so on.In some embodiments, the wearable medical system includes a singlesupport structure 110. In other embodiments, more support structures maybe included.

Support structure 110 can be dimensioned relative to the body of patient182 to be worn with internal tension 112. This dimensioning may beaccomplished by, for example, making a portion be of adjustable length.In other words, in some embodiments at some times support structure 110does not fit patient 182 everywhere loosely, but is worn with non-zerointernal tension 112. Tension 112 is tension of non-zero magnitude thatis internal to support structure 110, and which can cause pressure 114to be exerted onto the body of patient 182 when support structure 110 isworn. Pressure 114 may squeeze the body of patient 182, preferably onlygently. Internal tension 112, and its resulting pressure 114, may ensurethat any electrodes of the WCD system make good electrical contact withthe body of patient 182. Accordingly, support structure 110 can be acontinuous band, or have clasps (not shown) that lock together, etc.

Components 100 also include an electronics module 140. Electronicsmodule 140 can be a part of a wearable medical system that performs anyone or more of the following functions: monitor physiological signals ofpatient 182, make determinations from these signals, communicate withthe patient or with entities remote from the patient, store electricalenergy for defibrillation, defibrillate, and so on.

Electronics module 140 can be configured to be coupled to supportstructure 110. Coupling can be permanent, such as attaching. In someembodiments, however, electronics module 140 can be coupled to anduncoupled from support structure 110, by the manufacturer, by patient182, and so on. For example, electronics module 140 can be thus coupledby being inserted in a special pocket 111, and so on.

Components 100 additionally include an electrode 159, which can be anECG electrode. Electrode 159 can be stand-alone, or it may be attachedto an additional component 149 of an electrode assembly. Electrodeassemblies are described in more detail later in this document, and mayhave even more components. While only one electrode 159 is shown, ofcourse more may be used.

Whether part of an electrode assembly or not, electrode 159 can beconfigured to be coupled to support structure 110, so that electrode 159remains pressed against the body of patient 182 due to nonzero pressure114, when support structure 110 is worn by patient 182 as designed. Aswill be seen, a number of configurations of components 100 mayaccomplish this. For example, electrode 159 could be physically attachedto support structure 110, for example by being constructed permanentlyinto it, be received into a suitable pocket 115, etc. Moreover,electrode 159 could be coupled to support structure 110 but not bepermanently physically attached to it. Electrode 159 can be coupled tothe skin of patient 182 by contacting the skin directly, or indirectlyover clothing, depending on whether the electrode is dry or not, etc.Even when physically coupled to the skin over clothing, some electrodescan achieve electrical coupling with the patient's skin through theclothing.

Electrode 159 is of course conductive. This is written explicitly inthis document, because electrode 159 can be made according toembodiments from materials that are unusual for electrodes.

Electrode 159 may also be flexible. For example, it may bend underpressure 114. As can be seen in FIG. 2A, electrode 159 is flexibleenough so as to acquire a first shape due being subjected to nonzeropressure 114 when support structure 110 is worn by patient 182. Thefirst shape of FIG. 2A is bent, as flexible electrode 159 follows acurved contour of the body of patient 182. In FIG. 2A, support structure110 is shown even more abstractly than in FIG. 1. Due to theflexibility, electrodes according to embodiments can be integrated intoa support structure in such a way as to have fairly even pressure acrossthe complete electrode thereby reducing any perceived “pressure points”by the patient, and thus be more comfortable and increase patientcompliance.

In addition, as can be seen in FIG. 2B, electrode 159 is flexible enoughso as to acquire a second shape, if electrode 159 alone is deposited ona flat level surface 291 without being subjected to an externalpressure. The second shape is flat, which is different from the firstshape of FIG. 2A. Of course, to replicate the exact situation of FIG. 2Belectrode 159 may have to be separated from any electrode assembly. Theability to acquire the second shape so as to demonstrate the flexibilitycan sometimes be confirmed even without such a separation.

The flexibility of electrode 159 can be such that it transitions fromthe first shape to the second shape and vice versa immediately, or aftersome time. This time is preferably less than 1 hour, and preferably lessthan 10 min. Accordingly, hard materials like large pieces of metal maynot serve well.

The views of FIGS. 1, 2A, 2B are side views of electrode 159. Electrode159 may have a main surface, for example as shown in electrode 1159 inFIG. 11B. The main surface of electrode 1159 is shown as rectangular,but it can be circular, oval, or of other shapes. The main surface mayhave a surface area of, say, 1 cm² to several cm².

In some embodiments, electrode 159 may be 2 cm on the side. The amountof curvature shown in FIG. 2A may be larger than is the case for typicallocations of the body of patient 182, but the exaggeration in curvatureis used in FIG. 2A to demonstrate the flexibility of electrode 159.

The views of electrode 159 in FIGS. 1, 2A, 2B show its thickness,because they are side views. This thickness can be the height ofprotruding above the level of surface 291 in FIG. 2B. In embodiments,electrode 159 is further thin, which means it has a small thickness. Thethickness, then, can be measured in a direction perpendicular to themain surface. For example, electrode 159 may have an average thicknessof less than 4 mm, less than 2 mm, or even less than 1 mm, for example0.5 mm.

Electrode 159 may be made in a number of ways. For example, it caninclude a metal foil, such as aluminum or copper foil. Such a foil couldbe attached to a side of a piece of foam. Alternately, electrode 159 caninclude a material that includes polyurethane, or conductivepolyurethane that contains one of carbon, carbon nanotubes, particles ofa metal, and metal nanoparticles. Alternately, electrode 159 can includesilicone, a conductive silicone rubber, and so on. The conductivesilicone rubber may be enriched with conductive elements such as carbon,carbon nanotubes, particles of a metal, metal nanoparticles, and so on.Electrode 159 may also include a material that includespolydimethylsiloxane (PDMS) silicone rubber, perhaps enriched withconductive elements such as mentioned above. Electrodes formed fromsilicone rubber with added conductive fillers can be more resistive thancapacitive in nature. This resistive component allows for variousfeatures to be added that cannot be implemented with capacitiveelectrodes. First, the amplifier can generate a dc coupled driven leadwhich is used to reduce common mode on the patient. This is oftenreferred to as a Right Leg Drive though the electrode can be placed invarious places. Some capacitive electrodes cannot be used for drivenleads at frequencies that compensate for patient movement and power lineinterference. Using electrodes made from a silicone rubber greatlyincreases signal quality using driven leads. The resistive componentalso allows the use of a “dc leads off” method for detecting when anelectrode is not in good contact with the patient. This is both asimpler and more robust leads off method than the “ac leads off”required by capacitive electrodes. Embodiments of a silicone electrodecan thus be made without any electronics supporting the electrodeitself. In addition, electrodes thus formed from silicone rubber mightnot be affected much by commonly available lotions, and so the patientis free to use these both for general use or to minimize any effects ofusing the electrodes if the patient has very sensitive skin.

In choosing a material, care should be taken so that the materialcontacting the patient is biocompatible with the skin of the patient.Accordingly, if electrode 159 is worn over a garment, the material maynot matter very much. If, however, electrode 159 is configured tocontact the skin directly so it can make ohmic contact with it, then amaterial like aluminum may not be preferred. Ohmic contact makes forexcellent signal quality. The electrode could be made capacitive, ifneed be.

Returning to FIG. 1, components 100 may include a signal conductor 171.Signal conductor 171 can be configured to couple electronicallyelectronics module 140 and electrode 159 when electronics module 140 iscoupled to support structure 110 and support structure 110 is worn bypatient 182 as per the instructions for use. Signal conductor 171 mayinclude a wire, a cable and so on. It may be integrated with supportstructure 110 at least in part, for example retained by special loops ofit, suitable pockets of it, etc. Standard ECG cabling techniques can beused even with the silicone electrodes, because they generate a signalsimilar to that generated by a standard adhesive electrode.

FIG. 3 is a diagram of sample components 300 of a WCD system accordingto embodiments. Components 300 include an electronics module 340 thatcan be made as electronics module 140, and a support structure 310 thatcan be made as described for support structure 110, adapted fordifferences. Support structure 310 may include a suitable pocket 311 forelectronics module 340, and can be configured to be worn by a patient382. Support structure 310 can be dimensioned relative to a body ofpatient 382 to be so worn with nonzero internal tension 312, whichcauses nonzero pressure 314 to be exerted onto the body.

Components 300 additionally include an electrode assembly 350. Electrodeassembly 350 can be configured to be coupled to support structure 310 sothat electrode assembly 350 remains pressed against the body of patient382 due to nonzero pressure 314, when support structure 310 is worn bypatient 382. A number of configurations of components 300 may accomplishthis. For example, electrode assembly 350 could be physically attachedto support structure 310, for example by being constructed permanentlyinto it, be received into a suitable pocket 315, etc. Moreover,electrode assembly 350 could be coupled to support structure 310 but notbe permanently physically attached to it.

Electrode assembly 350 can be constructed in many different ways. It canhave components selected from many possible components. Examples are nowdescribed.

Referring to FIG. 4A, some components 450 are shown according toembodiments, which can be the components of electrode assembly 350.Components 450 include an electrode 459, which can be an ECG electrode.Electrode 459 can be made in any way known in the art, including waysdescribed earlier in this document for flexible electrode 159.

Components 450 additionally include a signal terminal 451. Inembodiments where electrode assembly 350 is removable from supportstructure 310, signal terminal 451 can advantageously be part of anelectro-mechanical connector. An electro-mechanical connector can beimplemented in many ways according to embodiments as is known in theart, for example with connector components that make a mechanicalconnection, and also complete an electrical connection upon making amechanical connection. These electro-mechanical connectors includeelements such as hooks, buttons, etc. Another example of anelectro-mechanical connector is a snap mechanical contact, which is alsoknown as a snap fastener. This snap mechanical contact may matchmatingly with another snap mechanical contact of support structure 310for coupling and uncoupling. For example, one can be male and the othercan be female.

Signal terminal 451 can be electrically coupled to electrode 459, whichis a feature not shown in FIG. 4A but is described later in thisdocument. This coupling should be made with a view to accommodating whatis physically between signal terminal 451 and electrode 459 in eachembodiment.

Returning to FIG. 3, components 300 may include a signal conductor 371.Signal conductor 371 can be configured to couple electronicallyelectronics module 340 and signal terminal 451 when electronics module340 is coupled to support structure 310 and support structure 310 isworn by patient 382. Signal conductor 371 may include a wire, a cableand so on, and may be integrated with support structure 310 as describedfor signal conductor 171. Signal conductor 371 may have a first end anda second end, to accomplish the coupling. For example, the first end ofsignal conductor 371 may terminate in a first electro-mechanicalconnector that is on support structure 310, and the signal terminal ofan electrode assembly that is electrically coupled to the electrode canbe part of a second electro-mechanical connector that can match matinglythe first electro-mechanical connector. The first electro-mechanicalconnector and the second electro-mechanical connector can be made asmentioned above, for example they can include snap mechanical contacts,etc.

Returning to FIG. 4A, components 450 additionally include a pillowstructure 456. Pillow structure 456 can be between electrode 459 andsignal terminal 451.

Pillow structure 456 can be flexible, and pressure 314 can maintain goodelectrical contact. The reduced pressure can thus help improve patientcompliance with wearing the WCD system. So, pillow structure 456 can beflexible enough so as to acquire a first shape due to the electrodeassembly being subjected to nonzero pressure 314 when support structure310 is worn. As seen in FIG. 4A, this first shape is somewhat flattened.As seen in FIG. 4B, pillow structure 456 can be flexible enough so as toacquire a second shape if pillow structure 456 alone is deposited on aflat level surface 491 without pillow structure 456 being subjected toan external pressure such as pressure 314. The second shape is differentfrom the first shape, it is less flattened. In this case, the firstshape is a squeezed version of the second shape. Of course, to replicatethe exact situation of FIG. 4B, pillow structure 456 may have to beseparated from the remainder of the electrode assembly. The ability toacquire the second shape as to demonstrate the flexibility can sometimesbe confirmed even without such a separation.

Pillow structure 456 may be made in a number of ways. For example, itcan include a piece of an open-celled foam, or a pouch filled with afluid, such as air, a liquid, etc. Foam works well when it is resilientenough, since it is a single material. In some embodiments, the pillowstructure includes a pouch that has a spring.

As mentioned above, an electrode assembly according to embodiments mayfurther include a flexible inner conductor. The signal terminal can beelectrically coupled to the electrode via the flexible inner conductor.For example, the flexible inner conductor can be electrically coupled tothe signal terminal, to the electrode, or to both. The flexible innerconductor may flex when pillow structure 456 transitions from the firstshape, e.g. of FIG. 4A, to the second shape, e.g. to that of FIG. 4B.Examples are now described.

Referring to FIG. 5, some components 550 are shown according toembodiments, which can be the components of electrode assembly 350.Components 550 include an electrode 559 that can be as described forelectrode 459, a signal terminal 551 that can be as described for signalterminal 451, and a pillow structure 556 that can be as described forpillow structure 456.

Components 550 moreover include a flexible inner conductor 553, which isa wire. Flexible inner conductor 553 is electrically coupled to bothsignal terminal 551 and to electrode 559.

Referring to FIG. 6A, some components 650 are shown according toembodiments, which can be the components of electrode assembly 350.Components 650 include an electrode 659 that can be as described forelectrode 459, a signal terminal 651 that can be as described for signalterminal 451, and a pillow structure 656 that can be as described forpillow structure 456.

Components 650 moreover include a flexible inner conductor 653, whichincludes a fabric. The fabric can operate as a flexible substrate, andbe advantageously coated with a metal, such as silver. Flexible innerconductor 653 is electrically coupled directly to signal terminal 651,and indirectly to electrode 659. In particular, flexible inner conductor653 is coupled to electrode 659 via a conductive adhesive 658.Alternately, a conductive double-sided pressure sensitive adhesive tapecould be used, etc. Or, electrode 659 could also be intrinsically moldedthrough or around the flexible conductor. Or, flexible inner conductor653 can include a conductive fabric that is overmolded with theelectrode.

Flexible inner conductor 653 can be planar. FIG. 6A shows only a sideview of it. Referring to FIG. 6B, a top view of conductor 653 is shown,where the fabric substrate is laid flat on a surface and the metalcoating is not differentiated. In this example, conductor 653 has alarge portion 684 that is substantially coextensive with the mainsurface of electrode 659, and a small portion 683 that is large enoughto make contact with signal terminal 651.

Referring to FIG. 7, some components 750 are shown according toembodiments, which can be the components of electrode assembly 350.Components 750 include an electrode 759 that can be as described forelectrode 459, a signal terminal 751 that can be as described for signalterminal 451, and a pillow structure 756 that can be as described forpillow structure 456.

Components 750 moreover include a moisture barrier 757. Moisture barrier757 is between electrode 759 and signal terminal 751. In this case wherepillow structure 756 is provided, moisture barrier 757 is betweenelectrode 759 and pillow structure 756.

In some embodiments, electrode 759 has a main surface that has holes.This feature is not shown in FIG. 7, but is shown in FIG. 11B.

Moisture barrier 757 of FIG. 7 is intended to not permit water vapor toescape from the patient's skin. The trapped water vapor improvesconductivity of the electrode, and the quality of the detected signal.

Accordingly, moisture barrier 757 is made from a material that issubstantially impermeable to water vapor so as to slow down theevaporation from the skin. This means that, if moisture barrier 757 ismade from a material that has pores, these pores are not large enough topermit the skin to dry out in the usual conditions that the patient isexpected to wear the WCD system. Candidates are any continuous-surfacematerial, even metal foil or a continuously coated water-resistantfabric material, such as the material that is sometimes used to makeraincoats. Other materials can be a thin polymer membrane, such as aurethane or silicone based material.

Referring to FIG. 8, some components 850 are shown according toembodiments, which can be the components of electrode assembly 350.Components 850 include an electrode 859 that can be as described forelectrode 459, a signal terminal 851 that can be as described for signalterminal 451, and a pillow structure 856 that can be as described forpillow structure 456.

Components 850 moreover include an electrostatic shield 855.Electrostatic shield 855 is between signal terminal 851 and electrode859. In this particular embodiment, electrostatic shield 855 is betweensignal terminal 851 and pillow structure 856. Electrostatic shield 855is intended to shield electrode 859 from any signals that may betraveling along any other signal conductors of the WCD system, and whichare physically close to the electrode assembly. Electrostatic shield 855may shield electrode 859 from varying electric fields that are externalto the patient. Such could be formed by clothing that has a staticcharge moving relative to electrode 859 or from another person who has astatic charge moving in close proximity to the patient. There are othersources of varying electric fields as well.

Electrostatic shield 855 can be made in a number of ways. Inembodiments, it can be made from a metal foil, such as copper.Electrostatic shield 855 is preferably protected from contacting theflexible conductor, and insulating is one way to do this. Accordingly,electrostatic shield 855 is sometimes a foil covered by an insulatingtape.

Referring to FIG. 9, some components 950 are shown according toembodiments, which can be the components of electrode assembly 350.Components 950 include an electrode 959 that can be as described forelectrode 459, a signal terminal 951 that can be as described for signalterminal 451, and a pillow structure 956 that can be as described forpillow structure 456.

Components 950 moreover include a cover 961. Cover 961 may surroundpillow structure 956 at least in part. In some embodiments cover 961 isflexible, and flexes when pillow structure 956 transitions from thefirst shape to the second shape. Cover 961 may be made from any suitablematerial, such as fabric, plastic, etc.

In some embodiments, cover 961 surrounds pillow structure 956completely. In other embodiments, the electrode assembly furtherincludes a backing which, together with cover 961, completely surroundpillow structure 956. An example is now described.

Referring to FIG. 10 an electrode assembly 1050 is shown, which is madeaccording to an embodiment. Electrode assembly 1050 is a standaloneelectrode assembly. Whether standalone or not, electrode assembly 1050can be used for electrode assembly 350.

Electrode assembly 1050 includes an electrode 1059 that can be asdescribed for electrode 459, a signal terminal 1051 that can be asdescribed for signal terminal 451, and a flexible inner conductor 1053that can be as described for flexible inner conductor 653. In thisparticular example, signal terminal 1051 can be part of a snapmechanical contact. Flexible inner conductor 1053 is electricallycoupled directly to signal terminal 1051, and indirectly to electrode1059 via a conductive adhesive 1058.

Electrode assembly 1050 also includes a pillow structure 1056 that canbe as described for pillow structure 456, a moisture barrier 1057 thatcan be as described for moisture barrier 757, and an electrostaticshield 1055 that can be as described for electrostatic shield 855.

Electrode assembly 1050 additionally includes a reference terminal 1052.Reference terminal 1052 is coupled to electrostatic shield 1055, and canserve as electrical ground. In this embodiment, reference terminal 1052can be part of a snap mechanical contact, similarly with signal terminal1051. In such embodiments, the WCD system may also include a referenceconductor 372, which can be seen in FIG. 3. Reference conductor 372 canbe configured to couple electronically electronics module 340 andreference terminal 1052, when electronics module 340 is coupled tosupport structure 310 and support structure 310 is worn by patient 382.

Electrode assembly 1050 moreover includes a backing 1054, on whichsignal terminal 1051 and reference terminal 1052 are provided. Backing1054 can be made from a hard plastic, or other suitable material. Thesnap mechanical contacts of signal terminal 1051 and reference terminal1052 are on backing 1054. These snap mechanical contacts permitelectrode assembly 1050 to be removable from the support structure.Signal terminal 1051 and reference terminal 1052 are electricallyconnected with wire stubs 1091, 1092 that go through suitable openingsin backing 1054.

Electrode assembly 1050 further includes a cover 1061 that can be asdescribed for cover 961. Backing 1054, together with cover 1061,completely surround pillow structure 1056.

In FIG. 10 the various components have been drawn with their appropriaterelationships. To improve clarity, space has been added between thecomponents that might not be there in actual embodiments. For example,wire stub 1091 can be shorter, and inner conductor 1053 may be touchingbacking 1054. Moreover, electrostatic shield 1055 might be attached toinner conductor 1053 and backing 1054, with wire stub 1092 beingaccordingly shorter. Pillow structure 1056 might be much larger, pushingmoisture barrier onto inner conductor 1053 and against electrode 1059,while uniformly stretching cover 1061. In fact, while inside the cover,pillow structure 1056 might be somewhat compressed compared to, say, howpillow structure 456 is shown in FIG. 4B.

Referring to FIG. 11A, some components 1150 are shown according toembodiments, which can be the components of electrode assembly 350.Components 1150 include an electrode 1159 that can be as described forelectrode 459, a signal terminal 1151 that can be as described forsignal terminal 451, and a moisture barrier 1157 that can be asdescribed for moisture barrier 757.

FIG. 11B is a top view of the main surface of electrode 1159. It will beobserved that electrode 1159 has holes or pores 1163. If moisturebarrier 1157 is indeed provided, it can cause moisture to be generatedfrom the skin as described above, which holes 1163 can capture.

Unlike with FIG. 7, components 1150 do not include a pillow structure,although it could. However, components 1150 may include other featuresthat were already described, for example an electrostatic shield 1255 asshown in FIG. 12 for electrode assembly components 1250, a cover 1361 asshown in FIG. 13 for electrode assembly components 1350, and so on.

Referring to FIG. 14, some components 1450 are shown according toembodiments, which can be the components of electrode assembly 350.Components 1450 include electrode 1459 that can be as described for anelectrode 459, a signal terminal 1451 that can be as described forsignal terminal 451, and an electrostatic shield 1455 that can be asdescribed for electrostatic shield 855.

Unlike with FIG. 8, components 1450 do not include a pillow structure.However, components 1150 may include other features that were alreadydescribed, for example a reference terminal 1552 as shown in FIG. 15 forelectrode assembly components 1550, and so on.

A person skilled in the art will be able to practice the presentinvention in view of this description, which is to be taken as a whole.Details have been included to provide a thorough understanding. In otherinstances, well-known aspects have not been described, in order to notobscure unnecessarily this description. Plus, any reference to any priorart in this description is not, and should not be taken as, anacknowledgement or any form of suggestion that such prior art formsparts of the common general knowledge in any country or any art.

This description includes one or more examples, but this fact does notlimit how the invention may be practiced. Indeed, examples, instances,versions or embodiments of the invention may be practiced according towhat is described, or yet differently, and also in conjunction withother present or future technologies. Other such embodiments includecombinations and sub-combinations of features described herein,including for example, embodiments that are equivalent to the following:providing or applying a feature in a different order than in a describedembodiment; extracting an individual feature from one embodiment andinserting such feature into another embodiment; removing one or morefeatures from an embodiment; or both removing a feature from anembodiment and adding a feature extracted from another embodiment, whileproviding the features incorporated in such combinations andsub-combinations.

In this document, the phrases “constructed to” and/or “configured to”denote one or more actual states of construction and/or configurationthat is fundamentally tied to physical characteristics of the element orfeature preceding these phrases and, as such, reach well beyond merelydescribing an intended use. Any such elements or features can beimplemented in a number of ways, as will be apparent to a person skilledin the art after reviewing the present disclosure, beyond any examplesshown in this document.

Any and all parent, grandparent, great-grandparent, etc. patentapplications, whether mentioned in this document or in an ApplicationData Sheet (ADS) of this patent application, are hereby incorporated byreference herein, including any priority claims made in thoseapplications and any material incorporated by reference, to the extentsuch subject matter is not inconsistent herewith.

In this description a single reference numeral may be used consistentlyto denote a single aspect, component, or process. Moreover, a furthereffort may have been made in the drafting of this description to choosesimilar though not identical reference numerals to denote versions orembodiments of an aspect, component or process that are the same orpossibly different. Where made, such a further effort was not required,but was nevertheless made gratuitously to accelerate comprehension bythe reader. Even where made in this document, such an effort might nothave been made completely consistently throughout the many versions orembodiments that are made possible by this description. Accordingly, thedescription controls. Any similarity in reference numerals may be usedto confirm a similarity in the text, or even possibly a similarity whereexpress text is absent, but not to confuse aspects where the text or thecontext indicates otherwise.

The claims of this document define certain combinations andsubcombinations of elements, features and steps or operations, which areregarded as novel and non-obvious. Additional claims for other suchcombinations and subcombinations may be presented in this or a relateddocument. These claims are intended to encompass within their scope allchanges and modifications that are within the true spirit and scope ofthe subject matter described herein. The terms used herein, including inthe claims, are generally intended as “open” terms. For example, theterm “including” should be interpreted as “including but not limitedto,” the term “having” should be interpreted as “having at least,” etc.If a specific number is ascribed to a claim recitation, this number is aminimum but not a maximum unless stated otherwise. For example, where aclaim recites “a” component or “an” item, it means that it can have oneor more of this component or item.

1-105. (canceled)
 106. A Wearable Cardiac Defibrillator (WCD) system,comprising: a support structure configured to be worn by a patient; anelectronics module; an electrode assembly configured to be coupled tothe support structure so that the electrode assembly is placed againstthe body when the support structure is so worn, the electrode assemblyincluding an electrode, a signal terminal electrically coupled to theelectrode, and a moisture barrier between the signal terminal and theelectrode, the electrode assembly further including a cover thatsurrounds the moisture barrier at least in part; and a signal conductorconfigured to couple electronically the electronics module and thesignal terminal when the electrode assembly is thus coupled to thesupport structure and the support structure is so worn.
 107. The WCDsystem of claim 106, in which the electrode includes a material thatincludes silicone.
 108. The WCD system of claim 106, in which theelectrode includes a material that includes a conductive siliconerubber.
 109. The WCD system of claim 106, in which the electrodeincludes a material that includes polydimethylsiloxane (PDMS) siliconerubber.
 110. The WCD system of claim 106, in which the electrode has amain surface that has holes.
 111. The WCD system of claim 106, in whichthe electrode assembly further includes an electrostatic shield betweenthe signal terminal and the electrode.
 112. The WCD system of claim 111,in which the electrostatic shield includes a metal foil covered by atape.
 113. The WCD system of claim 106, in which the cover surrounds themoisture barrier shield completely.
 114. The WCD system of claim 106, inwhich the electrode assembly further includes a backing which, togetherwith the cover, completely surround the moisture barrier.
 115. The WCDsystem of claim 106, in which the electrode assembly further includes anelectrostatic shield between the signal terminal and the electrode. 116.The WCD system of claim 115, in which the electrostatic shield includesa metal foil covered by a tape.
 117. A Wearable Cardiac Defibrillator(WCD) system, comprising: a support structure configured to be worn by apatient; an electronics module; an electrode assembly configured to becoupled to the support structure so that the electrode assembly isplaced against the body physically when the support structure is soworn, the electrode assembly including an electrode, a signal terminalelectrically coupled to the electrode, and an electrostatic shieldbetween the signal terminal and the electrode, the electrode assemblyfurther including a cover that surrounds the electrostatic shield atleast in part; and a signal conductor configured to coupleelectronically the electronics module and the signal terminal when theelectrode assembly is thus coupled to the support structure and thesupport structure is so worn.
 118. The WCD system of claim 117, in whichthe electrode assembly further includes a reference terminal coupled tothe electrostatic shield, and further comprising: a reference conductorconfigured to couple electronically the electronics module and thereference terminal when the electrode assembly is thus coupled to thesupport structure and the support structure is so worn.
 119. The WCDsystem of claim 117, in which the cover surrounds the electrostaticshield completely.
 120. The WCD system of claim 117, in which theelectrode assembly further includes a backing which, together with thecover, completely surround the electrostatic shield.
 121. A WearableCardiac Defibrillator (WCD) system, comprising: a support structureconfigured to be worn by a patient; an electronics module; an electrodeassembly configured to be coupled to the support structure so that theelectrode assembly is placed against the body when the support structureis so worn, the electrode assembly including an electrode, the electrodeincluding a material that includes a conductive silicone rubber, theelectrode assembly further including a signal terminal electricallycoupled to the electrode, and a moisture barrier between the signalterminal and the electrode; and a signal conductor configured to coupleelectronically the electronics module and the signal terminal when theelectrode assembly is thus coupled to the support structure and thesupport structure is so worn.
 122. A Wearable Cardiac Defibrillator(WCD) system, comprising: a support structure configured to be worn by apatient; an electronics module; an electrode assembly configured to becoupled to the support structure so that the electrode assembly isplaced against the body when the support structure is so worn, theelectrode assembly including an electrode, the electrode including amaterial that includes polydimethylsiloxane (PDMS) silicone rubber, theelectrode assembly further including a signal terminal electricallycoupled to the electrode, and a moisture barrier between the signalterminal and the electrode; and a signal conductor configured to coupleelectronically the electronics module and the signal terminal when theelectrode assembly is thus coupled to the support structure and thesupport structure is so worn.
 123. A Wearable Cardiac Defibrillator(WCD) system, comprising: a support structure configured to be worn by apatient; an electronics module; an electrode assembly configured to becoupled to the support structure so that the electrode assembly isplaced against the body when the support structure is so worn, theelectrode assembly including an electrode, the electrode having a mainsurface that has holes, the electrode assembly further including asignal terminal electrically coupled to the electrode, and a moisturebarrier between the signal terminal and the electrode; and a signalconductor configured to couple electronically the electronics module andthe signal terminal when the electrode assembly is thus coupled to thesupport structure and the support structure is so worn.
 124. A WearableCardiac Defibrillator (WCD) system, comprising: a support structureconfigured to be worn by a patient; an electronics module; an electrodeassembly configured to be coupled to the support structure so that theelectrode assembly is placed against the body when the support structureis so worn, the electrode assembly including an electrode, a signalterminal electrically coupled to the electrode, and a moisture barrierbetween the signal terminal and the electrode, the electrode assemblyfurther including an electrostatic shield between the signal terminaland the electrode, the electrostatic shield including a metal foilcovered by a tape; and a signal conductor configured to coupleelectronically the electronics module and the signal terminal when theelectrode assembly is thus coupled to the support structure and thesupport structure is so worn.
 125. A Wearable Cardiac Defibrillator(WCD) system, comprising: a support structure configured to be worn by apatient; an electronics module; an electrode assembly configured to becoupled to the support structure so that the electrode assembly isplaced against the body physically when the support structure is soworn, the electrode assembly including an electrode, a signal terminalelectrically coupled to the electrode, an electrostatic shield betweenthe signal terminal and the electrode, and a reference terminal coupledto the electrostatic shield; a signal conductor configured to coupleelectronically the electronics module and the signal terminal when theelectrode assembly is thus coupled to the support structure and thesupport structure is so worn; and a reference conductor configured tocouple electronically the electronics module and the reference terminalwhen the electrode assembly is thus coupled to the support structure andthe support structure is so worn.